Neurodegenerative diseases such as Parkinson's disease, Alzheimer's disease and Huntington's disease are caused by the death of neurons. As used herein, the term “neurodegenerative” refers to the loss or death of neurons causing the disease. Typically, neurodegenerative diseases are characterized by a slow onset and chronic progression. In a neurodegenerative disease, a particular part of the brain, spinal cord, or peripheral nerve functionally fails and the neurons of the dysfunctional region die. Neurodegenerative diseases are often categorized by whether they initially affect cognition, movement, strength, coordination, sensation, or autonomic control. However, it is not uncommon for patients to be presented with symptoms and signs to more than one system. While it is possible that involvement of several systems can occur concomitantly, typically by the time the patient has functionally declined enough to seek medical attention multiple systems have become involved. Diagnosing neurodegenerative diseases can prove particularly intimidating to clinicians, because many times the diagnosis cannot be critically “confirmed” by a simple test.
The prevalence of neurodegenerative diseases has increased drastically. In fact, it is estimated that currently Alzheimer's disease is now the sixth leading cause of death in the U.S.
Accordingly, there is an urgent need for effective treatments of neurodegenerative diseases.